1. Field of the Invention
The present invention relates to an improvement of a fuel injection valve supporting structure in which: a nozzle portion at a front end portion of a fuel injection valve is fitted in an injection valve attachment hole of an engine; a fuel supply cap of a fuel distribution pipe supported by the engine is fitted on a fuel introduction portion at a rear end portion of the fuel injection valve; a supporting member for biasing the fuel injection valve toward the injection valve attachment hole is interposed between the fuel injection valve and the fuel supply cap.
2. Description of the Related Art
Such a fuel injection valve supporting structure is already known, as disclosed in Japanese Patent Application Laid-open No. 2004-245168.
With regard to such a conventional fuel injection valve supporting structure, a U-shaped plate spring as a supporting member is interposed between a fuel injection valve and a fuel supply cap. In this kind of fuel injection valve supporting structure, the support of the fuel injection valve may become unstable because: stress concentrates particularly on a bent portion of the U-shaped plate spring; and as a long time passes, the bent portion plastically deforms and the set load of the plate spring decreases.